The primary functions of Cell Therapy Core are to assist Projects 2-6 by making available critical equipment and technical expertise covering three distinct aspects of research support: optimal cryopreservation and storage of canine and human cells;characterization of canine transplantation products by flow cytometry;and stem cell enrichment from canine components. Specifically, this Core will: (A) store peripheral blood and/or serum specimens obtained from dogs and humans exposed to varying doses of irradiation as part of biodosimetry development Projects 2 and 3, and create a canine cord blood bank in support of Project 5. (B) Enrich for canine CD34+ cells to be used as the starting material for the ex vivo expanded myeloid progenitor cell studies described in Projects 4 and 5. As part of these projects the development of more optimized cryopreservation and storage conditions for these types of cells will also be necessary. (C) Analyze by flow cytometry all the various canine components used for transplantation as part of Projects 4-6. This proposed Cell Therapy Core represents an enhancement of an already existing Cell Processing resource that has considerable expertise in each of these areas. The existing resource manages several Research and Clinical Cell Repositories that contain a variety of cell types, encompassing over 50,000 different specimens stored in the vapor phase of liquid nitrogen freezers, including components used to support human therapeutic studies. The Processing Core has performed over 30 canine CD34+ cell enrichments, achieving excellent purities of >80% and yields of 50%. Finally, the Core specializes in flow cytometry analysis, and has established a database with over 3500 human clinical transplant components characterized for the content of hematopoietic stem cells (CD34), T-cell subsets (CDS, CD4, CDS, CD45RA), dendritic cells (CD14, BDCA-2), B-cells (CD19, CD22) and NK cell (CD56) subsets. These data form the basis for important correlative studies to investigate associations of these cell types with several clinical outcomes. In summary, Cell Therapy Core D will provide unique and critical services in support of Projects 2-6 described in this grant application, specifically optimal cryopreservation and storage, cell selection, and flow cytometry analysis, and will be able to provide those services in a more efficient and cost-effective manner.